1. Field of the Invention
The present invention relates to an output apparatus such as a printer connected to a host computer through a bidirectional interface, and a method therefor.
2. Related Background Art
A printer always requires certain consumable materials. For example an ink jet printer requires ink sealed in an ink cartridge. Also an output apparatus for forming an image on a sheet by the electrophotographic technology utilizes toner for color development. In the following description, such consumable materials, including ink, will be exemplified by toner. As the toner is consumed in the printing operation, it has to be replenished by the user. For facilitating such toner replenishing operation, the toner packaged in a cartridge is widely employed in recent printing apparatus. When the toner in the cartridge is used up, the user removes the empty toner cartridge from the printing apparatus and replaces it with a new toner cartridge.
As the printing operation can naturally be no longer executed when the toner is used up, a warning mechanism is often employed to provide the user with a prior warning before the toner is completely exhausted. For example a mechanical sensor, provided in the toner cartridge, detects a low remaining amount of the toner and displays a warning on the liquid crystal display of the printing apparatus or sends a status signal to the host computer, thereby giving the user a warning through the monitor of the host computer.
Recognizing such prior warning, the user can take various measures such as preparing or purchasing a toner cartridge, avoiding the output operation for a large job, or increasing the density of the output image.
Also in case the printing apparatus has to discriminate the toner cartridges of different kinds, the shape of such cartridge is made partly different according to the kinds and such difference is detected by a mechanical sensor provided in the printing apparatus.
However, such conventional method of mechanically detecting the remaining toner amount is capable of detecting that the remaining toner amount has reached a certain level, but is associated with a drawback that the remaining amount thereafter or the running-out time of the toner cannot be known at all.
In consideration of the foregoing, an object of the present invention is to exactly recognize or estimate the remaining amount of the recording material until it becomes completely exhausted.
Another object of the present invention is to provide the user with a warning for the low remaining amount of the recording material, in a form convenient and easily understandable to the user.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus for effecting printing operation utilizing a cartridge of the recording material, the apparatus comprising detection means for detecting the remaining amount in the cartridge, a recording material cartridge provided with non-volatile memory means, and control means for recognizing the remaining amount of the recording material by storing the cumulative consumed amount of the recording material in the non-volatile memory means of the recording material cartridge.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means which obtains the consumed amount of the recording material from the cumulative number of the used dots.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising calculation means which obtains the cumulative consumed amount of the recording material by estimating the consumed amount of the recording material per dot according to whether the recording material is used in each dot, and, if used, whether the recording material is used in an adjacent dot, among the entire dots on a sheet, thereby estimating the total consumed amount of the recording material per sheet, and by accumulating the consumed amount of the recording material of the different pages.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means for obtaining the cumulative consumed amount of the recording material, for characters, by multiplying the average dot number per font provided in the output apparatus with the number of characters in each font, and, for the fonts for which the average dot number per font is not available and for non-character images, by counting the number of used dots.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means which compares the anticipated consumed amount of the recording material with the actual consumed amount when the remaining amount of the recording material becomes actually low in the recording material cartridge, then stores the error information in the non-volatile memory means of the cartridge and incorporates such error information in the subsequent estimation of the consumed amount of the recording material, thereby achieving exact estimation of the consumed amount thereof.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means which in advance stores information on the average consumed amount of the recording material per page for each kind of sheet and obtains the consumed amount of the recording material by multiplying each kind of sheet with the number of pages.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means which estimates the consumed amount of the recording material from the number of the low remaining states of the recording material in the recording material cartridge.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means which in advance stores information, for each component of the recording material cartridge, on the number of sheets for which such component is usable, in the non-volatile memory means of the recording material cartridge, and which is adapted to provide a warning that each component has been used for such number of sheets.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means which has plural warnings depending on the remaining amount of the recording material and adapted to suitably provide such plural warnings.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means capable of providing a warning, such as for the absence of the recording material, in different timings, according to the frequency of use of the printing apparatus.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means capable of providing a warning, such as for the absence of the recording material, in different timings, according to the consumed amount in each page.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means capable of releasing, at the absence of the recording material, an arbitrary message stored in the non-volatile memory means of the recording material cartridge.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means capable storing the actual consumed amount of the recording material in the non-volatile memory means of the recording material cartridge and transmitting the stored content in response to a user operation on the printing apparatus or a request from the host computer.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means which stores the expiry date of the recording material in the non-volatile memory means thereof and generates a warning when the expiry date of the cartridge is reached.
The above-mentioned objects can be attained, according to the present invention, by an output apparatus comprising control means which stores the date information, when the recording material cartridge is first used, in the non-volatile memory means thereof and generates a warning when the life of the cartridge expires after such first use.